Collapsible pressure ring



Dec. 5, 1933. p O'BRIEN I 1,938,437

COLLAPSIBLE PRESSURE RING Filed Feb. 5, 1930 2 Sheets-Sheet 2 HHHIHIIHHHINVENTOR 7 /12/174 Z. O'Brien TTORNEY Patented Dec. 5, 1933 UNITED"Si-Ares ear-EMT OFFICE oormrsrsne PRESSURE RING Philip 1.. .OBrien,Ohelmsford, Miss. Application February 5, 1930. 7 Serial No. 425,931 i-claim (o1. 1s 1s 10 to insert or remove. The object or my invention isto provide a ring of this, character which is both easy to insert andeasy to remove, and a further object is to make the so that it will bestrong enough to withstand all the stresses without injury. Yet anotherobject is to provide such a ring, which can be provided withattachments, which permit it to be used with any of several sizes ofvtires. These and other objects are accomplished byrny invention,

one embodiment of which is hereinafter more particularly set forth. 4

For a more detailed description of my invention, reference is to behadto the accompan ing drawin s, forming apart hereof, in which Figure 1shows my improved ring with a portion of an air bag resting thereon, it.being understood that when in use, such a bag extends entirely aroundthe circumference;

Figure 2 is a sectional View talren on the line 3 2--2 of Figure 1,looking in the direction of the arrow;

Figure 3 shows a hinge Figure 4 shows the ring in its folded condition;1

Figure 5 shows a tool operating to close the ring so as to lock the samein the bag;

Figure 6 is a corresponding view with the tool reversed showing theposition it occupies just prior to being used for opening the jointbetween two parts of the ring whereby may 40 be removed from the ring;and, w

Figure 7 is a sectional view showing how a device may be attached forwidening the ring so that it may be used on a tire of different crosssection.

Throughout the various views of the drawings, similar referencecharacters designate similar parts.

1 is a bag of any suitable size according to the interior of the tire itis to fit. It is well known in the trade as a D shaped bag, because incross section it is in the form of the letter D. 2 is my improved ringwhich will now be described in detail.

This ring 2 has four sections in the embodi- 55- merit shown which willbe designated by the characters 3, 4, 5, and 6 respectively. More orless of these sections may be used as desired, although in the preferredembodiment four are employed.

It is of importance thatthese sections be of 9" different lengths sothat they will fold together as indicated in Figure 4, where 4 is thelongest 5 is the next in length.- y 6 is the shortest and 3 comesbetween 5 and 6 in length. Each of these sections consists of a segmentof a circle with inwardly projecting flanges 7 which structure resultsin a very rigid construction with a minimum amount of metal. This is ofreat importance because of the extreme pressures to which these ringsare subjected. such as 150 pounds per square inch. and even-more, andthis is the ordinary working pressure for a ring of the diameter oftwenty-five to twentyseven inches and it is obvious that great strengthis required as theultimate pressure on this ring 5 is very great indeed.

The sections are connected by identical hinges so that a descriptionofone will answer for all. These hinges 8 have two leaves 9 BandlOconnected by a pin-11, which has its axisjat thejSQ-L inner edges of theflanges. '7, and these parts are very sturdy and strong and securelyriveted. in place by rivets 12. These. hinges are made. and. set true sothat the parts will properlycoact when the ring is expanded and inplace.

Two hooks 13 are also used and these are pl ced at, adjacent ends ofthepartsS andfi andthese hooks have their openings facing each otherwhen the parts are in the positicns shown in Figures 5 and 6. Thesehooksare preferably. shaped substantially as shown and made" very firmand strong and fixed. to their respective" segments by suitable rivets14. vThe base of the hook 13 on the segment 6 is projected-beyond;

this segment forabout three-quarters of an inch as indicatediat 15, andpassed between theends or" two angle-irons 16 on the segment 3. Theseangle-irons 16 may be given any suitable cross section, but arepreferably made of section known as T iron, and these are held bysuitable rivets 1'7. Corresponding irons 18 held by rivets 19' are fixedto. the part 6, but stop short of the end so as to abut against theirons 16, when the parts are assembled as shown in Fi ures 1 and 3.

These parts, when assembled as above described, 5'

have a firm tongue and groove joint which looks these parts togetherwith sufficient firmness, it being understood that all the workingpressure on the ring is exerted from the bag 1 and towards the centre.The stresses are all com- 0 pressing stresses. These angle-irons 16 and18 give the essential strength at the joint, and also facilitate in thelocking, above described.

The means for locking and unlocking will now be described. The hooks 13are shaped so as to receive pins 19 which are located at the ends of ahand lever 20 which is pivotally connected at 21 to a link 22 so thatwhen it is desired to close the ring, the parts are assembled as shownin Figure 5 and the lever is thrown as indicated by the arrow, andthereafter the ring is expanded until the tongue 15 and angle-iron 16can clear the opposing parts, and thereafter the pressure of the bag isexerted to draw all parts together to the position indicated in Figure6, the bag being slightly stretched for this purpose. When the ring isto be opened with a view to its removal, the lever 20 is put in reverseposition, as shown in Figure 6, and then the movement is reversed andthe tongue 15 and angle-irons 16 are again cleared with a reversemovement when the lever is thrown as indicated by the arrow. It isimportant that the fulcrum 21 should'be nearer the pin 19 on the lever20 than it is to the pin 19 on the link 22, because this structure givesa leverage favorable to the operation as above described. The bestresults are obtained with proportions about as shown.

In view of the foregoing, the operation of my device will be readilyunderstood, assuming the parts to be constructed and used as aboveindicated. The bag 1 is deflated, if this has not yet been done, and putinto the shoe or casing which is to be vulcanized and retreaded, andthen the ring is put inside the shoe and looked, as above described soas to back up the bag. Thereafter, when the tire is placed in the mouldand on the lower part of a matrix where it rests, the upper part of thematrix is then put in place and clamped. Thereafter, the air bag 1 isinflated to the requisite pressure, say one hundred pounds per squareinch, and thereafter the heat which is on the vulcanizer begins tofunction and vulcanizes the new rubber for the necessary time. Afterthis vulcanization is completed, the

bag is deflated, the clamps are removed and the upper part of the matrixis removed, and then the shoe with the bag and ring therein are removedand the ring is then collapsed as above described and taken out of thebag and shoe and thereafter the bag is removed and then this operationmay be repeated on another shoe.

It is sometimes desirable to operate with tires of the same diameter butof greater cross section and then it is necessary to re-enforce thecorrespondingly enlarged bag which is employed. This isdone by putting acylindrical circle 23, as indicated in Figure 7, on the periphery of thesegments, each of these being bent into an arc of the right shape andlength and given the width desired and each is held in place by means ofa bolt 24 which is preferably provided with a wing nut 25 and in thepreferred embodiment of my invention this bolt has a square shank 26which fits in a correspondingly square hole 27 found in each of thesegments above described.

While I have shown and described some embodiments of my invention, it isobvious that it is not restricted thereto, but that it is broad enoughto cover all structures that come within the scope of the annexedclaims.

Having thus described my invention, what I claim is:

1. A collapsible pressure ring composed of a number of segments hingedtogether with two free ends and means for causing said ends to lock orinterlock and cylindrical plates, one on each segment, and means forlocking the plates to their respective segments.

2. A collapsible pressure ring having a plurality of segments hingedtogether, two of the segments having free ends for interengagement tohold the various segments together in the form of an annulus, one of thefree ends having a groove defined by spaced plates projecting from itsconcave face, the other free end having a projecting tongue for entryinto said groove, each of the ends having a hook member disposed on itsconcave face for engagement by a tool to force the tongue and grooveinto interlocking relationship.

3. A collapsible pressure ring having a plurality of segments hingedlyconnected, two of the segments having free ends for interengagement tohold the various segments together in the form of an annulus, one of thefree ends having spaced arcuate plates secured to its concave face, saidplates forming a groove between them, the other free end also havingspaced arcuate plates and a tongue located between them and adapted forentry into the groove inv the other free end, and means for receiving atool by which the tongue and groove may be forced into interlockingrelationship.

4. A collapsible pressure ring having a plurality of segments hingedlyconnected, two of the segments having free ends for placement togetherin interlocking relationship to hold the various segments in the form ofan annulus, one of the free ends having spaced arcuate plates secured toits concave face, said plates forming a groove between them, the otherfree end also having spaced arcuate plates and a tongue located betweenthem and adapted for entry into the groove in the other free end, a hookshaped member projecting from the tongue, and a hookshaped-memberlocated in the groove, said hookshaped members receiving a tool by whichthe tongue and groove are forced together into interlockingrelationship.

PHILIP L. OBRIEN.

